Aries wasnt evil. He was the god of war but in war heroes are made, glory blah blah blah. It wasnt the death that he relished so much as the battle itself. The vikings werent evil but carried similar beliefs. The Huns would be another example. Just a different outlook on war.
And Discord was Jealous and insulted that she wasnt chosen to be in a sort of goddess beauty contest. So she caused a war. Not evil misguided. Teenagers girls throw tantrums and do things without regard for others well being all the time.
My biggest point though is that gods for the most part did not consider a loss of human life a loss at all. Humans were beneath them. They would lament the death of a human the same way we lament the death of a squirrel in the road.
